JP4751590B2 - Electronic imaging device - Google Patents

Description

  The present invention relates to an electronic image pickup apparatus, and more particularly to an electronic image pickup apparatus including a photographing optical system that includes an optical path bending optical system and has a zooming function.

  In recent years, a subject image formed by a photographing optical system composed of a plurality of optical lenses is photoelectrically converted into an electric signal using an image pickup device such as a CCD (Charge Coupled Device), and the resulting electric signal is obtained. 2. Description of the Related Art An electronic imaging device such as a digital camera configured to record a typical image signal as image data such as digital data on a recording medium or the like is widely used.

  An imaging optical system applied in a conventional electronic imaging apparatus is composed of a plurality of optical lenses as described above. Each of these optical lenses can perform a zooming operation (zooming operation) and a focus adjustment operation (focusing operation) by arbitrarily moving each of them in the direction along the optical axis.

  For this purpose, each optical lens constituting the photographing optical system is held by a frame member. Each of these frame members is linked by a cam coupling or the like, and a lens barrel is configured by a plurality of frame members formed so as to cooperate with each other, driving means for driving the frame members, and the like.

  Thus, in the conventional lens barrel in which a plurality of frame members and the like are individually driven by the cam mechanism, the shape of each frame member and the like tends to be complicated. Therefore, an electronic imaging device configured using this has a limit in realizing a reduction in manufacturing cost and a reduction in size of the device itself.

On the other hand, in recent electronic imaging devices, there is a strong demand for further thinning. Therefore, as one means for realizing thinning of the apparatus itself, for example, a reflecting member such as a reflecting mirror or a prism is disposed in the optical path of the photographing optical system, and the optical path is bent using this reflecting member to the image sensor side. There are various proposals that have been made to lead to the above and have been put to practical use. In an electronic imaging apparatus that employs such an optical path bending optical system, since the length of the optical system can be reduced, effective means for realizing a reduction in thickness and size of the electronic imaging apparatus; It has become.
JP 2003-107356 A JP 2003-302567 A JP 2004-102090 A JP 2004-170707 A

  However, according to the conventional technical means described in each of the above-mentioned publications, for example, a mechanism for connecting a plurality of lens groups in the optical axis direction at the time of zooming operation is related to conventional electronic imaging. The configuration is the same as that of the optical system in the apparatus. Therefore, it is considered difficult to simplify the structure.

  As described above, when the optical path bending optical system is adopted as the photographing optical system, the lens group is not drawn out from the electronic image pickup apparatus, but it is necessary to displace a plurality of lens groups in the apparatus, so that the entire apparatus is thin. It becomes difficult to reduce the size and size.

  The present invention has been made in view of the above-described points, and an object of the present invention is to provide an electronic imaging apparatus including a lens barrel that includes an optical path bending optical system and has a zooming function. It is an object of the present invention to provide an electronic imaging apparatus capable of realizing further downsizing and thinning of the apparatus itself while simplifying the structure.

In order to achieve the above object, an electronic image pickup apparatus according to the present invention includes a first optical system that is disposed closest to a subject and transmits a light beam from the same subject and transmits the light beam that passes through the first optical system. An electronic imaging apparatus comprising: a second optical system that bends an optical path; and an imaging element that receives an optical image of a subject formed through the first optical system and the second optical system and converts the optical image into an electrical signal. characterized in, when cormorants as to put the zooming operation, while fixing the second optical system, and this with a driving means Before moving the said first optical system and the image pickup device along the optical axis And

  According to the present invention, in an electronic image pickup apparatus including a lens barrel having an optical path bending optical system and having a zooming function, the structure of the lens barrel is simplified, and the apparatus itself is further reduced in size and thickness. An electronic imaging device that can be realized can be provided.

  The embodiment of the present invention shown in the drawings will be described below.

  FIG. 1 is a perspective view showing a schematic appearance of an electronic imaging apparatus according to an embodiment of the present invention. FIG. 2 is a block configuration diagram showing a schematic internal configuration of the electronic imaging apparatus of FIG. 3 and 4 are longitudinal sectional views showing the lens barrel unit of the electronic imaging apparatus shown in FIG. Among these, FIG. 3 shows the retracted state of the lens barrel unit. FIG. 4 shows a shooting state of the lens barrel unit, which is set to a short focal position. FIG. 5 is a conceptual diagram showing the operation of the photographing optical system and the image pickup element unit when the zooming operation is executed in the electronic image pickup apparatus of FIG. FIG. 6 is a diagram illustrating the operation of the photographing optical system and the image pickup element unit when the zooming operation is executed in the electronic image pickup apparatus of FIG. 1, and is a diagram illustrating the conceptual diagram of FIG. 5 according to the present embodiment.

  The external configuration of the electronic imaging apparatus 1 of the present embodiment is as shown in FIG. That is, the electronic imaging apparatus 1 includes an exterior member 10 that covers and protects various internal components (see FIG. 2), which will be described later, and a lens mirror that is movably disposed at a substantially central portion of the front surface of the exterior member 10. A tube 12, a flash light emitting window 16 of a flash light emitting device (not shown) provided at a predetermined portion on the front side of the exterior member 10 and irradiating a subject with an illumination light beam, and provided on the upper surface side of the exterior member 10. Various operation members (release button 13, zooming operation lever 14, operation mode switching button 15, power on / off button (not shown), etc.) and a liquid crystal display (LCD) provided on the back side of the exterior member 10 It is mainly comprised by the display apparatus (not shown) etc. which consist of etc.

  The lens barrel 12 includes a photographing optical system 12a that includes a plurality of optical lenses and forms an optical image of a subject, a plurality of frame members (33, 34) that respectively hold the photographing optical system 12a, and the frame members. Is composed of a plurality of frame members (31, 32) and the like that advance and retreat in a direction along the optical axis O (see FIG. 2) of the photographing optical system 12a (detailed configuration will be described later, see FIGS. 3 and 4).

  As shown in FIG. 2, the photographing optical system 12a is a first optical lens that is disposed on the front side of the electronic imaging apparatus 1 and closest to the subject, and includes a plurality of optical lenses that allow light beams from the subject to enter and pass therethrough. The first lens group 21 is an optical system, and the second optical system 22 is disposed behind the first lens group 21 and bends the optical path of a light beam that passes through the first lens group 21.

  Here, the second optical system 22 is arranged behind the first lens group 21 and behind the second lens group 22a. The second lens group 22a is arranged coaxially with the optical axis O. It includes a reflecting mirror 22b that is a surface mirror having a reflecting surface that serves to bend the optical axis O (see FIG. 2) of the photographing optical system 12a and change the traveling direction of the optical path. A shutter mechanism 26a is disposed between the second lens group 22a and the reflecting mirror 22b. The number of optical lenses used in the first lens group 21 and the second lens group 22a is two in this embodiment. However, the number of optical lenses is not limited to this. It may be more than one.

  When the electronic imaging apparatus 1 is in the photographing state, the reflecting mirror 22b is on the intersection line with the optical axis O of the first lens group 21 and the second lens group 22a, and has an angle of approximately 45 with respect to the optical axis O. It is designed to be tilted by a certain degree. In this state, the reflecting surface of the reflecting mirror 22b is disposed toward the subject so as to receive an incident light beam that passes through the first lens group 21 and the second lens group 22a. As a result, the incident light beam transmitted through the first lens group 21 and the second lens group 22a is reflected in a predetermined direction by the reflecting mirror 22b, so that the optical path is bent at an angle of approximately 90 degrees, and desired. Direction, i.e., toward the image sensor unit 23 described later.

  In addition, the reflecting mirror 22b is configured to retreat out of the optical path of the light beam that passes through the first lens group 21 and the second lens group 22a when the electronic imaging apparatus 1 is in a non-photographing state. In the space formed after the reflecting mirror 22b is retracted, at least a part of the second lens group 22a is accommodated (details will be described later, see FIG. 3).

  Note that the image sensor unit 23 in the electronic image pickup apparatus 1 of the present embodiment is a photoelectric conversion element that receives an optical image of a subject formed by the photographing optical system 12a and converts it into an electrical signal. 23a, a cover glass 23b made of a transparent member that covers and protects the light-receiving surface of the image sensor 23a, and a light beam from a subject that is disposed in a stacked manner on the front surface of the cover glass 23b, thereby allowing the image sensor 23a to pass therethrough. A low-pass filter (LPF) 23c that removes a high-frequency component from the light flux incident on the light receiving surface is integrally formed.

  The light receiving surface of the image pickup device unit 23 is disposed in parallel with the bottom surface in the exterior member 10 of the electronic image pickup apparatus 1. Therefore, when the electronic imaging device 1 of the present embodiment is in the shooting state, the subject luminous flux incident from the subject on the front side of the device 1 is reflected after being transmitted through the first lens group 21 and the second lens group 22a. By being reflected by the mirror 22b in a predetermined direction, the optical path is bent and guided to the light receiving surface of the imaging element unit 23 on the bottom surface side of the electronic imaging device 1. Thereby, a subject image corresponding to the subject is formed on the light receiving surface of the image sensor 23 a of the image sensor unit 23.

  On the other hand, the internal configuration of the electronic imaging apparatus 1 is as shown in FIG. That is, inside the electronic imaging apparatus 1, there are a control circuit 20 that comprehensively controls the electrical circuits and components of the electronic imaging apparatus 1, and the various operation members (release button 13, zooming lever). 14, various operation switches (first (1st) release switch 30b, second (2nd) release) that generate an instruction signal corresponding to each operation member in conjunction with an operation mode switching button 15, a power on / off button, etc. (see FIG. 1) Switch 30c, zoom switch 30a, mode switch 30d, power on / off switch 30e, etc.) and the respective lens groups (21, 22a) of the photographing optical system 12a are driven as required based on the control signal of the control circuit 20. The optical system driving mechanism 24 including the first group driving unit 24a and the second group driving unit 24b, and the light beam after being bent by the reflecting mirror 22b. Based on the control signal from the control circuit 20, the image sensor unit 23 is arranged to be movable along the optical axis O2 (see FIGS. 3 and 4). The image pickup system drive mechanism 25 to be moved, the shutter drive mechanism 26 that drives the shutter mechanism 26a based on the control signal of the control circuit 20, and the drive control of the image pickup device unit 23 based on the control signal of the control circuit 20. And an image processing circuit 27 that receives an output signal from the image sensor unit 23 and performs predetermined image signal processing, and is optimal for receiving an output signal from the image processing circuit 27 and recording it on a recording medium (not shown). Image storage for forming various types of image data or reading image data recorded on a recording medium and converting the image data into an optimal image signal for display on a display device A road 28, is mainly constituted by a display circuit 29 for displaying on the display device (not shown) display unit the corresponding image in response to an output signal from the image processing circuit 27.

  Further, inside the electronic image pickup apparatus 1, a lens configured by a lens barrel 12 including a photographing optical system 12 a and an image sensor unit housing portion 41 including an image sensor unit holding frame 43 that holds the image sensor unit 23. A lens barrel unit 51 is provided.

  In the following description, the optical axis incident on the photographing optical system 12a is a first optical axis O1, and the optical axis after being reflected by the reflecting mirror 22b is a second optical axis O2.

  Here, the configuration of the lens barrel unit 51 will be described below with reference to FIGS. 3 and 4.

  3 shows the retracted state of the lens barrel 12, and the first lens group 21 and the second lens group 22a which is a part of the second optical system 22, and each lens frame (rotating frame, rectilinear frame, The first group frame) is in the storage position, and the reflecting mirror 22b is in the retracted position retracted from the optical path.

  FIG. 4 shows a short focal position which is one of the photographing states of the lens barrel 12, and the first lens group 21 and the second lens group 22a which is a part of the second optical system 22, and each lens frame which will be described later. The (rotating frame, rectilinear frame, first group frame) is at the photographing position, and the reflecting mirror 22b is at the reflecting position that has entered the optical path.

  The lens barrel 12 constituting the lens barrel unit 51 includes a fixed frame 31 that is disposed on the outermost peripheral side and has a substantially cylindrical shape, and a rotary frame 32 that is provided on the inner peripheral side of the fixed frame 31 and has a substantially cylindrical shape. A first group frame 33 which is provided on the inner peripheral side of the rotary frame 32 and has a substantially cylindrical shape and holds the first lens group 21, and a second cylinder which is provided on the inner peripheral side of the rotary frame 32 and has a substantially cylindrical shape. A rectilinear frame 34 that holds the second lens group 22a and the shutter mechanism 26a that are part of the optical system 22, and a reflecting mirror 22b that is disposed inside the fixed frame 31 and constitutes part of the second optical system 22. Is mainly constituted by a mirror frame 35 or the like that is fixedly held and is rotatable in a predetermined direction (the direction of arrow R in FIGS. 3 and 4).

  The fixed frame 31 has, on its inner peripheral surface, a female helicoid 31a formed on substantially the entire inner periphery, and three rectilinear grooves that extend in the direction along the optical axis O1 and are formed at substantially equal intervals in the circumferential direction. 31 b and a circumferential groove 31 c formed in the vicinity of the tip edge portion.

  Further, the opening on the rear end side of the fixed frame 31 is shielded by the lid member 37. The lid member 37 is fixed to the rear edge portion of the fixed frame 31 by a plurality of screws 37a.

  A male helicoid 32 a that is screwed into the female helicoid 31 a of the fixed frame 31 is formed in the vicinity of the rear edge on the outer peripheral side of the rotating frame 32. As a result, the fixed frame 31 and the rotating frame 32 are helicoidally coupled. When the rotary frame 32 is rotationally driven by a predetermined driving means, the rotary frame 32 moves forward and backward in the direction along the optical axis O1 while rotating with respect to the fixed frame 31.

  When the rotating frame 32 is drawn out by a predetermined amount, the male helicoid 32 a of the rotating frame 32 is engaged with the circumferential groove 31 c of the fixed frame 31. In this state, the rotary frame 32 is restricted from advancing and retracting in the direction along the optical axis O1 while maintaining a state of being rotatable with respect to the fixed frame 31. Thereby, the movement of the rotation frame 32 in the direction along the optical axis O1 is restricted and is set in a fixed state.

  Further, on the inner peripheral surface of the rotary frame 32, a circumferential groove 32b and three cam frames 32c for a single group frame formed at substantially equal intervals in the circumferential direction are formed in the vicinity of the rear edge portion.

  The rectilinear frame 34 is a frame member having a substantially cylindrical shape as described above, and is configured by fixing and holding the second lens group 22a on the inner peripheral side thereof. A shutter mechanism 26a is integrally provided on the rear end side, and a shutter lid member 26b having a shape capable of passing the light beam transmitted through the second lens group 22a while covering and covering the shutter mechanism 26a is disposed. It is installed. Thereby, the shutter mechanism 26a moves integrally with the second lens group 22a.

  A pressing pin 34d is planted on the rear end surface of the rectilinear frame 34 so as to protrude rearward in the direction along the optical axis O1.

  On the front end face of the rectilinear frame 34, there is an aperture stop 34c that restricts the incidence of a light beam that is not required for photographing by restricting the optical path width of the transmitted light beam incident on the second lens group 22a. It is fixed.

  The rectilinear frame 34 includes a rectilinear key 34a projecting from the rearmost edge of the outer peripheral surface thereof at substantially equal intervals in the circumferential direction, and in the vicinity of the rectilinear key 34a and inside the rectilinear key 34a. Are formed with three bayonet claws 34b protruding so as to be substantially equidistant in the circumferential direction.

  The rectilinear key 34 a is adapted to engage with the rectilinear groove 31 b of the fixed frame 31. Accordingly, the rotation of the rectilinear frame 34 with respect to the fixed frame 31 is restricted thereby.

  Further, the bayonet claw 34 b is engaged with the circumferential groove 32 b of the rotating frame 32, so that the rotating frame 32 and the rectilinear frame 34 are connected with the bayonet. Accordingly, the rectilinear frame 34 can rotate about the optical axis O1 with respect to the rotating frame 32, and at the same time, can move forward and backward integrally with the rotating frame 32 in the optical axis O1 direction.

  Furthermore, three rectilinear grooves 34e extending in a direction along the optical axis O1 and formed at substantially equal intervals in the circumferential direction are formed through the inner peripheral side of the rectilinear frame 34.

  As described above, the first group frame 33 is a frame member having a substantially cylindrical shape, and the first lens group 21 including a plurality of optical lenses is fixedly held on the inner peripheral side thereof. Three cam followers 33a are planted toward the outer periphery of the first group frame 33 in the vicinity of the rear end edge on the outer peripheral side at substantially equal intervals in the circumferential direction. These cam followers 33a pass through the rectilinear grooves 34e of the rectilinear frame 34 and engage with the cam grooves 32c for the first frame of the rotary frame 32. Accordingly, the rotation of the first group frame 33 is restricted with respect to the rectilinear frame 34, and the cam follower 33a moves along the first group frame cam groove 32c as the rotation frame 32 rotates. The first group frame 33 is movable back and forth in the direction along the optical axis O1.

  According to the present embodiment, the first group drive unit 24a, which is the first group lens drive mechanism in the optical system drive mechanism 24, is mainly configured by a cam mechanism of the first group frame cam groove 32c and the cam follower 33a. The On the other hand, the second group drive unit 24b, which is the second group lens drive mechanism in the optical system drive mechanism 24, is mainly composed of a helicoid mechanism of a female helicoid 31a and a male helicoid 32a. However, the first group lens driving mechanism and the second group lens driving mechanism are not limited to this, and can be configured by combining, for example, a cam mechanism, a helicoid mechanism, a feed screw mechanism, and the like as appropriate.

  On the other hand, inside the fixed frame 31, as described above, the mirror frame 35 on which the reflecting mirror 22b constituting a part of the second lens group 22 is fixedly held is disposed. One end of the mirror frame 35 is rotatably supported with respect to a support shaft 35a fixed to a predetermined fixing member (not shown). The mirror frame 35 is always urged counterclockwise along the arrow R by the urging member 36 with the support shaft 35a as the rotation center in FIGS.

  The reflecting surface of the reflecting mirror 22b disposed in the mirror frame 35 is disposed in the direction in which the second lens group 22a is disposed.

  When the electronic imaging apparatus 1 is in a non-photographing state, that is, in the retracted state shown in FIG. 3, the mirror frame 35 resists the urging force of the urging member 36 by a pressing pin 34 d provided on the rectilinear frame 34. It will be in the state pushed backward. At this time, the reflecting mirror 22b of the mirror frame 35 is disposed inside the fixed frame 31 at the retracted position retracted from the optical axis O1 and the optical axis O2, as shown in FIG.

  Further, when the electronic imaging apparatus 1 is in a photographing state, that is, in the state shown in FIG. 4, the rectilinear frame 34 is disposed at a position advanced with respect to the fixed frame 31. For this reason, the mirror frame 35 is arranged at a predetermined portion inclined forward by the urging force of the urging member 36. That is, as described above, the reflecting mirror 22b of the mirror frame 35 is located on the intersection line with the optical axis O1, and is inclined by about 45 degrees with respect to the optical axis O1. In this state, the reflecting mirror 22b becomes a reflection position that has entered the optical path along the optical axes O1 and O2.

  In the fixed frame 31, the image sensor unit storage portion 41 is disposed so as to extend in a direction orthogonal to the optical axis O <b> 1. The imaging element unit storage portion 41 is, for example, a cylindrical portion formed in a substantially cylindrical shape, and the light beam reflected by the reflecting mirror 22b passes through a portion connected to the fixed frame 31 on one end side thereof. A through-hole 41c serving as an optical path (optical axis O2) is formed.

  Further, the opening on the other end side of the image sensor unit housing portion 41 is shielded by the lid member 42. The lid member 42 is screwed to the other end edge portion of the image sensor unit housing portion 41 with a plurality of screws 42a.

  Inside the image sensor unit housing portion 41, the image sensor unit 23 is disposed so as to be movable in a direction along the optical axis O2 (the arrow Y direction shown in FIGS. 3 and 4).

  Note that the image sensor unit housing portion 41 may be formed integrally with the fixed frame 31, or may be configured such that a member separate from the fixed frame 31 is attached to the fixed frame 31. And the image pick-up element unit accommodating part 41 is arrange | positioned in the dimension which the fixed frame 31 occupies in the optical axis O1 direction. Thereby, the increase in the dimension of the lens barrel unit 51 in the optical axis O1 direction can be prevented. Further, the thickness of the electronic imaging device 1 itself can be reduced, which can contribute to downsizing.

  The moving mechanism of the image sensor unit 23 is configured as follows. That is, the image sensor unit 23 is held by the image sensor unit holding frame 43. A first support arm 43 a and a second support arm 43 c are formed on the outer peripheral edge portion of the image sensor unit holding frame 43 at positions facing each other.

  One first support arm 43a is provided with a through hole 43b penetrating in the direction along the optical axis O2. Further, a nut 25c constituting a part of the imaging system driving mechanism 25 is integrally disposed on the outer peripheral surface of the first support arm 43a. The guide shaft 44 is inserted through the through hole 43b. The guide shaft 44 is stretched in the direction along the optical axis O <b> 2 inside the image sensor unit housing portion 41, between the lid member 42 and the fixing portion 41 a facing the lid member 42. A coiled spring 46 that is an extensible biasing member is wound around the guide shaft 44 around a portion between the image sensor unit holding frame 43 and the lid member 42. Thereby, the image sensor unit holding frame 43 is always urged toward the side where the reflecting mirror 22b is disposed inside the image sensor unit housing portion 41. Further, the coil spring 46 serves to remove the movement play in the direction along the optical axis O2 of the image sensor unit holding frame 43.

  The imaging element unit holding frame 43 is driven in the direction of the optical axis O2 by the imaging system driving mechanism 25. That is, the nut 25c is integrally fixed to the first support arm 43a of the image sensor unit holding frame 43 as described above. A lead screw 25b is screwed into the nut 25c. The lead screw 25b is integrally fixed to the rotating shaft of the stepping motor 25a. In this case, the lead screw 25b is suspended so as to be rotatable with respect to a fixing base 25d fixed to a fixing portion inside the imaging element unit storage portion 41. The stepping motor 25a connected to the lead screw 25b is fixed to the fixed base 25d.

  That is, the imaging system drive mechanism 25 is configured by the stepping motor 25a, the lead screw 25b, the nut 25c, and the fixed base 25d. The driving force of the imaging system driving mechanism 25 is coupled so as to be transmitted to the imaging element unit holding frame 43.

  The other second support arm 43c is formed with a rotation stop groove 43d. A rotation stop shaft 45 similar to the above-described guide shaft 44 is inserted into the rotation stop groove 43d. That is, the rotation stop shaft 45 is also in the image sensor unit housing portion 41, and in the direction along the optical axis O2 between the lid member 42 and the fixing portion 41b facing the lid member 42. It is stretched so as to be substantially parallel to the guide shaft 44. As a result, the imaging element unit holding frame 43 is restricted in rotation in the rotation direction around the guide shaft 44 and can slide smoothly in the direction along the optical axis O2. Yes.

  With such a configuration, the rotational driving force by the stepping motor 25a rotates the lead screw 25b that is coaxially fixed to the rotation shaft. Then, the rotational driving force of the lead screw 25b is transmitted to the nut 25c that is screwed to the lead screw 25b. Thereby, the nut 25c moves in the direction along the optical axis O2. Accordingly, at this time, the image pickup device unit holding frame 43 to which the nut 25c is fixed is restricted by the rotation stop shaft 45 and is guided in the direction along the optical axis O2 (arrow Y direction). It moves along 45.

  The operation of the electronic imaging apparatus 1 according to the embodiment configured as described above will be described below.

  The photographing optical system 12a held by the lens barrel 12 of the electronic imaging apparatus 1 according to the present embodiment is composed of a plurality of optical lenses as described above, and can change the focal length arbitrarily within a predetermined range. This is a variable power lens system configured so that operation (so-called zooming) can be performed freely.

  Further, at the time of non-photographing, the lens barrel 12 is in a contracted state so that the photographing optical system 12a is stored in the apparatus 1 (referred to as a retracted state).

  On the other hand, at the time of photographing, the lens barrel 12 is extended from the retracted state to a predetermined position, that is, the shortest focal length (shortest focal length) that can be set in the lens barrel 12 is set (short focal length). The lens barrel 12 is expanded and contracted within a predetermined range from a state set to the longest focal length that can be set in the lens barrel 12 (referred to as a long focus state). Double operation can be performed.

  Note that the short focus state described above refers to a state in which the photographing optical system 12a is in the short focus position and a wide angle position (wide end position) is set, for example. Further, the above-described long focus state refers to a state in which the photographing optical system 12a is at the long focus position, and a telephoto position (tele end position) is set, for example.

  In this case, the photographing optical system in a general electronic imaging apparatus performs an operation as shown in FIG. That is, FIG. 8 is a conceptual diagram showing the positional relationship between the photographing optical system and the image pickup element unit when a scaling operation is executed in a conventional electronic image pickup apparatus.

  First, each lens group of the imaging optical system 112a is moved from the retracted state shown in FIG. 8A to a short focus state shown in FIG. 8B by a driving operation by a predetermined optical system driving mechanism. Here, the photographing optical system 112a is composed of a first lens group 121 and a second lens group 122. The image sensor unit 123 is fixed at a predetermined site on the optical axis O of the photographing optical system 112a.

  In the short focus state shown in FIG. 8B, the distance between the first lens group 121 and the second lens group 122 is L1w, and the optical path distance between the second lens group 122 and the imaging surface of the imaging element unit 123 is L2w. It has become.

  Next, each lens group of the photographing optical system 112a is moved so as to change from the short focus state shown in FIG. 8B to the long focus state shown in FIG. 8C. Then, in this long focus state, the distance between the first lens group 121 and the second lens group 122 is L1T, and the optical path distance between the second lens group 122 and the imaging surface of the imaging element unit 123 is L2T.

  As described above, in the conventional electronic imaging apparatus, the imaging element unit 123 is fixed and each of the lens groups (the first lens group 121 and the second lens group 122) constituting the imaging optical system 112a is moved. The scaling operation is executed with.

  In the focus adjustment operation in each zooming state, for example, a part of each lens group constituting the photographing optical system 112a is driven. Therefore, the lens barrel that holds the photographic optical system 112a requires a complicated drive mechanism that can drive each lens group in accordance with the zooming operation and the focus adjustment operation.

  On the other hand, in the electronic imaging device 1 of the present embodiment, an operation as shown in FIG. 5 is performed. FIG. 5 is a conceptual diagram showing the positional relationship between the imaging optical system and the imaging element unit when the zooming operation is executed in the electronic imaging apparatus of this embodiment.

  First, each lens group of the photographing optical system 12a is moved from the retracted state shown in FIG. 5A to a short focus state shown in FIG. 5B by a driving operation by a predetermined optical system driving mechanism. Here, the photographing optical system 12a includes a first lens group 21 and a second lens group 22a. An imaging element unit 23 is disposed at a predetermined site on the optical axis O2 of the photographing optical system 12a.

  In the present embodiment, when the short focus state shown in FIG. 5B is set, the second lens group 22a is fixed, and the first lens group 21 and the image sensor unit 23 are aligned along the optical axes O1 and O2. Can move freely.

  In the short focus state shown in FIG. 5B, the distance between the first lens group 21 and the second lens group 22a is L1w, and the optical path distance between the second lens group 22a and the imaging surface of the imaging element unit 23 is L2w. It has become. At this time, each of the optical path intervals L1w and L2w is equivalent to the optical path intervals L1w and L2w shown in FIG.

  Next, each lens group of the photographing optical system 12a is moved so as to change from the short focus state shown in FIG. 5B to the long focus state shown in FIG. 5C. During this moving operation, the second lens group 22a is fixed as described above.

  In the long focus state of FIG. 5C, the distance between the first lens group 21 and the second lens group 22a is L1T, and the optical path distance between the second lens group 22a and the imaging surface of the imaging element 23a is L2T. ing. At this time, each of the optical path intervals L1T and L2T is equivalent to the optical path intervals L1T and L2T shown in FIG.

  In the focus adjustment operation in each zooming state, the image sensor unit 23 is displaced along the optical axis O2. Therefore, the lens barrel driving mechanism can be simplified as compared with the conventional one. In addition, it is easy to realize the drive mechanism for zooming operation and the drive mechanism for focus adjustment of the image sensor unit 23 with a single drive mechanism.

  In the present embodiment, the image sensor unit 23 is moved in the direction of the optical axis O2 during the zooming operation and the focus adjustment operation. However, only the image sensor 23a may be driven.

  Further, the feed amount Zd from the retracted position of the first lens group 21 to the most extended position (short focus position in the present embodiment) can be made smaller than the feed amount Zd0 shown in FIG. This is to fix the second lens group 22a that is at least a part of the second optical system 22 during zooming operation, and drive the first lens group 21 in the direction of the optical axis O1 with respect to the second lens group 22a. This is because the image sensor unit 23 is driven with respect to the second lens group 22a.

  That is, in the conventional form shown in FIG. 8, the extension amount Zd0 of the first lens group 121 includes a change in the optical path interval between the second lens group 122 and the image sensor 123. On the other hand, according to the present embodiment, the driving amount of the first lens group 21 includes the amount of change in the optical path interval between the second lens group 22a and the image pickup device unit 23, and hardly extends. This is because the amount Zd is set.

  As described above, in the electronic imaging device 1 according to the present embodiment, the extension amount of the lens group can be reduced, so that the size in the optical axis O1 direction of each lens frame constituting the lens barrel can be reduced.

  In the present embodiment, the image sensor unit 23 is moved in the direction along the optical axis O2. However, the mechanism for moving the image sensor unit 23 in the same direction can be realized with a simpler mechanism than the mechanism for relatively moving a plurality of lens groups.

  Next, the configuration of each lens group constituting the photographing optical system 12a applied in the electronic imaging device 1 of the present embodiment will be described below.

  As described above, the electronic imaging apparatus 1 adopts the variable magnification lens system as the photographing optical system 12a. This zoom lens system is configured as a two-group zoom lens in which a first lens group 21 having a negative refractive power and a second lens group 22a having a positive refractive power are arranged in order from the object side. . During zooming operation, the first lens group 21 is movable and the second lens group 22a is fixed. Thus, the focal distance can be changed by changing the air gap between the first lens group 21 and the second lens group 22a. The second lens group 22a is movable from a position in the retracted state to a position set at the short focus (or long focus) end in the shooting state.

  Here, FIG. 6 is a diagram showing the action of the photographing optical system and the image pickup device when the zooming operation is executed in the electronic image pickup apparatus of FIG. 1, and the conceptual diagram of FIG. 5 is based on this embodiment. Show.

  FIG. 6A shows a state in which the photographing optical system 12a (variable magnification lens system) is stored inside the electronic imaging apparatus 1, that is, a retracted state.

  FIG. 6B shows a short focus state of the photographing optical system 12a (variable magnification lens system).

  FIG. 6C shows a state in which an intermediate focal length that can be set by the photographing optical system 12a (variable magnification lens system) is set. The state at this time is a state at the standard focus position, or a standard (or intermediate) focus state in which an intermediate state (standard position) is set.

  FIG. 6D shows a long focus state of the photographing optical system 12a (variable magnification lens system).

  As shown in FIG. 6, the imaging optical system 12a changes from the retracted state of FIG. 6 (A) to the short focus state of FIG. 6 (B), passes through the intermediate focus state of FIG. 6 (C), and passes through the intermediate focus state of FIG. As the long focus state is reached, the distance between the first lens group 21 and the second lens group 22a moves so as to become narrower.

  At this time, the positive second lens group 22a is fixed to the fixed frame 31 (see FIGS. 3 and 4) as described above, while the first lens group 21 is incident on the second lens group 22a. It is movable along the optical axis O1 on the side (see FIGS. 3 and 4).

  As described above, the second lens group 22a includes the aperture stop 34c, the plurality of optical lenses including the positive lens and the negative lens, the shutter mechanism 26a, and the fixing member of the electronic imaging apparatus 1 during the zooming operation. It has a reflecting mirror 22b that is fixed, and is configured to bend the incident optical path from the subject by an angle of about 90 degrees and guide it toward the image sensor unit 23 by the reflecting action of the reflecting surface of the reflecting mirror 22b. Has been.

The low-pass filter 23c, the cover glass 23b, and the image pickup device 23a are integrally arranged on the optical axis O2 (see FIGS. 3 and 4) in the form of being arranged in order from the incident side (object side) of the light beam.

  Then, the image sensor unit 23 is disposed so as to be able to move in a direction along the optical axis O2 at a position where the light beam reflected by the reflecting mirror 22b can be received. The position of the image sensor unit 23 is determined in conjunction with the movement of the image plane position set by the movement of the first lens group 21.

  In the retracted state of FIG. 6 (A), the reflecting mirror 22b and the mirror frame 35 that holds the reflecting mirror 22b are stored inside the fixed frame 31 at positions retracted from the optical axis O1 and the optical axis O2. It has become.

  At this time, the aperture stop 34c of the second lens group 22a, the optical lens composed of a positive lens and a negative lens, and the shutter mechanism 26a are integrally stored. Further, in this state (the state shown in FIG. 3 or FIG. 5A), the first lens group 21 is retracted inside the electronic imaging apparatus 1 by gradually narrowing the distance from the second lens group 22a. It has become.

  On the other hand, details of each lens group in the present embodiment will be described in more detail below.

The first lens group 21 is configured by arranging a negative meniscus lens having a convex surface facing the object side and a positive meniscus lens having a convex surface facing the object side in order along the optical axis O1 from the object side. . The second lens group 22a includes a biconvex positive lens and a negative meniscus lens having a convex surface facing the image side.

  The aspheric surfaces are used for a total of five surfaces including the image-side surface of the negative meniscus lens of the first lens group 21 and all the lens surfaces of the second lens group 22a.

  The reflecting mirror 22b uses a surface mirror. When the reflecting mirror 22b is in a photographing state, its reflecting surface is disposed at a position 4 mm from the top of the exit surface of the negative lens of the second lens group 22a and is at an angle of 45 degrees with respect to the optical axis O. It is arranged with an inclination.

  The aperture stop 34c disposed on the object side of the positive lens of the second lens group 22a is set to a fixed circular stop. And the edge part which determines the axial light beam of this aperture stop 34c is set as the structure located in the reflective surface side rather than the surface vertex of the positive lens of the 2nd lens group 22a.

  With this configuration, the moving range of the first lens group 21 used for the zooming operation can be increased, which is advantageous for increasing the zoom ratio or reducing the camera thickness during wide-angle shooting.

  In addition, even in the condensing state, the dimension of the photographing optical system 12a in the optical axis direction can be reduced, which is an advantageous configuration for reducing the thickness of the electronic imaging device 1 in the thickness direction (depth direction). ing.

  In the electronic imaging device 1 of the present embodiment, the light amount adjustment during the photographing operation is performed by a mechanical shutter mechanism 26a disposed on the image side of the negative lens of the second lens group 22a.

  Apart from this, for example, a system in which the imaging time during the imaging operation is adjusted by the image sensor unit 23 may be used without using the shutter mechanism 26a. In such a configuration, the arrangement of the shutter mechanism 26a can be omitted, which is a more advantageous configuration for reducing the thickness of the device 1 during the retracting operation.

  Further, in the electronic imaging apparatus 1, a focus adjustment operation (AF operation; focusing) for a short-distance object point moves the imaging element unit 23 in a direction along the optical axis O2 in a direction away from the reflecting surface of the reflecting mirror 22b. It will be done. Alternatively, the first lens group 21 may be moved toward the object side in the direction along the optical axis O1.

The numerical data of the one embodiment will be shown below. In this case,
f: Total focal length F _No : F number WE: At wide-angle end shooting ST: At intermediate focal length shooting TE: At telephoto end shooting r1, r2, ...: Curvature radius of each lens surface d1, d2, ...: Each lens Distance between surfaces on optical axis nd1, nd2, ...: Refractive index of d-line of each lens νd1, νd2, ...: Abbe number of each lens. The aspherical shape can be expressed by the following equation, where x is the optical axis with the light traveling direction being positive, and y is the direction orthogonal to the optical axis.

^{x = (y 2 / r)} / [1+ {1- (K + 1) (y / r) 2} 1/2] + A4y 4 + A6y 6 + A8y 8
In this case,
r: paraxial radius of curvature K: conic coefficient A4: fourth-order aspheric coefficient A6: sixth-order aspheric coefficient A8: eighth-order aspheric coefficient Note that the shutter position and the reflecting surface position are omitted from the numerical data.

r1 = 54.1696 d1 = 1.0000 nd1 = 1.74320 νd1 = 49.34
r2 = 4.8359 (aspherical surface) d2 = 1.6143
r3 = 6.5785 d3 = 1.6421 nd2 = 1.84666 νd2 = 23.78
r4 = 9.7896 d4 = (variable)
r5 = ∞ (aperture) d5 = −0.3000
r6 = 4.4880 (aspherical surface) d6 = 2.0086 nd3 = 1.49700 νd3 = 81.54
r7 = −5.2355 (aspherical surface) d7 = 0.6212 nd4 = 1.68893 νd4 = 31.08
r8 = −4.2761 (aspherical surface) d8 = 2.5138
r9 = −12.1262 (aspherical surface) d9 = (variable)
r10 = ∞ d10 = 0.9600 nd5 = 1.54771 νd5 = 62.84
r11 = ∞ d11 = 0.6000
r12 = ∞ d12 = 0.5000 nd6 = 1.51633 νd6 = 64.14
r13 = ∞ d13 = 0.5000
r14 = ∞ (image plane)
Aspheric coefficient 2nd surface
K = −0.3732
A4 = 1.1763 × 10 ^-4
A6 = 7.6055 × 10 ^-6
A8 = 0.0000
6th page
K = 0
A4 = −4.8314 × 10 ^-4
A6 = −1.8704 × 10 ^-5
A8 = 0.0000
7th page
K = 0
A4 = 5.4417 × 10 ^-3
A6 = −1.4828 × 10 ^-4
A8 = 0.0000
8th page
K = 0
A4 = 8.7473 × 10 ^-3
A6 = −2.3686 × 10 ^-4
A8 = 0.0000
9th page
K = 0
A4 = 3.8519 × 10 ^-3
A6 = 9.6677 × 10 ^-5
A8 = 0.0000
Zoom data (∞)
WE ST TE
f (mm) 6.0150 11.9944 17.3441
F _NO 3.1115 4.1841 5.1487
d4 12.9832 4.1430 1.4000
d9 8.3569 13.0706 17.3669
The operation of the electronic imaging apparatus 1 of the present embodiment configured as described above is as follows.

  A user of the electronic imaging apparatus 1 operates a power on / off button (not shown) among various operation members when the electronic imaging apparatus 1 is in a power-off state (collapsed state). 1 is activated. As a result, the electronic imaging device 1 shifts from a retracted state during non-photographing to a photographing preparation state in which photographing can be performed. The operation at this time is as follows.

  First, when the electronic imaging apparatus 1 is in a power-off state, the user turns on a power on / off button of the electronic imaging apparatus 1. Then, the power on / off switch 30e (see FIG. 2) linked to the power on / off button is activated to generate a power on signal, and the power on signal is transmitted to the control circuit 20. In response to this, the control circuit 20 initializes each circuit of the electronic imaging apparatus 1 and then drives the optical system driving mechanism 24 to prepare the photographing for the lens barrel 12 (the photographing optical system 12a) from the retracted state. Move to the shortest focal position, which is the initial position of the state. The operation of the lens barrel 12 and the like at this time is as follows.

  That is, in the state of FIG. 3, when the optical system driving mechanism 24 is driven, the rotary frame 32 rotates in a predetermined direction (feeding direction). Since the male helicoid 32a of the rotating frame 32 meshes with the female helicoid 31a of the fixed frame 31, the rotating frame 32 rotates with respect to the fixed frame 31 in a direction along the optical axis O1 toward the front. It is paid out. As the rotary frame 32 is extended, the rectilinear frame 34 and the first group frame 33 also move in the same direction. At this time, the rectilinear frame 34 is rotatable about the optical axis O1 with respect to the rotating frame 32, and at the same time, can advance and retract integrally with the rotating frame 32 in the direction along the optical axis O1. .

  Since the rectilinear frame 34 is restricted from rotating around the optical axis O1 with respect to the fixed frame 31, the rectilinear frame 34 is fed out together with the rotating frame 32 in the optical axis O1 direction without rotating around the optical axis O1.

  When the rotating frame 32 is drawn out by a predetermined amount, the male helicoid 32 a of the rotating frame 32 engages with the circumferential groove 31 c of the fixed frame 31. As a result, the rotary frame 32 is restricted from moving back and forth in the direction along the optical axis O <b> 1 while maintaining a rotatable state with respect to the fixed frame 31. Thereby, the rotation frame 32 is restricted from moving in the direction along the optical axis O1 and is in a fixed state.

  Therefore, the movement in the optical axis O1 direction of the rectilinear frame 34 that is integrally displaced in the optical frame O1 direction with the rotary frame 32 is limited. Then, the second lens group 22a is extended from the storage position to the photographing position together with the rectilinear frame 34.

  On the other hand, with the rotation of the rotary frame 32 around the optical axis O1, the first group frame 33 is extended in the direction of the optical axis O1 by the cam coupling action between the first group frame cam groove 32c and the cam follower 33a. The second lens group 22a is separated from the second lens group 22a by a predetermined amount, for example, corresponding to the wide end of the photographing optical system 12a.

  When the rotating frame 32 is further rotated from this state, the rotating frame 32 and the rectilinear frame 34 are not moved forward and backward in the optical axis O1 direction, and the first group frame 33 is displaced in the optical axis O1 direction and the first lens group 21 is moved. The distance from the second lens group 22a changes, and a zooming operation is performed.

  Further, with the operation of feeding the rotating frame 32 at this time, the pressing of the mirror frame 35 by the pressing pin 34d is gradually released. Therefore, the mirror frame 35 is a direction along the direction of the arrow R in FIGS. 3 and 4 with the support shaft 35a as the rotation center by the urging force of the urging member 36 as the rectilinear frame 34 is drawn forward. And it turns counterclockwise. Then, when the feeding of the rectilinear frame 34 is stopped, the mirror frame 35 also stops its rotation at a predetermined position and becomes a reflection position. In this stopped state, the mirror frame 35 is in a state where one end is in contact with the pressing pin 34d by the urging force of the urging member 36. Thereby, the urging | biasing to the rotation direction of the mirror frame 35 is controlled, The mirror frame 35 is positioned in the position (position shown in FIG. 4). The reflecting mirror 22b of the mirror frame 35 at this time has a substantially central portion disposed in the vicinity of the intersection of the optical axis O1 and the optical axis O2, and tilted by 45 degrees with respect to each of the optical axis O1 and the optical axis O2. Set to

  In this way, the electronic imaging device 1 is set to the short focus state, which is the initial position of the shooting preparation state.

  In this state, the user performs various settings prior to the shooting operation, for example, a selection operation for a desired shooting mode and a scaling operation for setting a desired shooting screen.

  That is, the user performs switching setting to a desired operation mode by operating the operation mode switching button 15 among various operation members. When the operation mode switching button 15 is operated, the mode switch 30d interlocked therewith is operated to generate a mode switching signal, and this mode switching signal is transmitted to the control circuit 20. In response to this, the control circuit 20 performs predetermined signal processing and performs a switching control operation to an operation mode corresponding to the input mode switching signal.

  In addition, when the user operates the zoom operation lever 14, the zoom switch 30 a that operates in conjunction therewith operates to generate a zoom signal, and this zoom signal is transmitted to the control circuit 20. In response to this, the control circuit 20 performs forward / backward drive control of the first group frame 33 (first lens group 21) and the image sensor unit 23 via the first group drive unit 24a of the optical system drive mechanism 24 and the imaging system drive mechanism 25. To do. Thereby, the photographing optical system 12a is set to a desired focal length.

  In this way, when various settings for shooting are completed, the user next performs an operation of executing a shooting operation.

  In this case, the user performs a pressing operation of the release button 13. When the release button 13 is pressed, first, the first release switch 30b is activated by the first-stage pressing operation, and the 1st. A release signal is generated. The release signal is transmitted to the control circuit 20. This 1st. The release signal is an instruction signal for starting an automatic exposure operation (AE operation) or an automatic focus adjustment operation (AF operation), for example.

  In response to this, the control circuit 20 controls the image processing circuit 27 to execute the AE operation or acquire information for executing the AF operation. At the same time, the control circuit 20 controls the imaging system driving mechanism 25 based on the acquired various information. An AF operation is executed under drive control. When the AF operation is performed by moving the first lens group 21, the first group driving unit 24 a of the optical system driving mechanism 24 is driven and controlled here.

  Subsequently, when the release button 13 is further pressed and the second-stage pressing operation of the button 13 is performed, the second release switch 30c is activated and 2nd. A release signal is generated, and this 2nd. The release signal is transmitted to the control circuit 20. 2nd. The release signal is an instruction signal for starting an exposure operation for acquiring an image. In response to this, the control circuit 20 controls the image processing circuit 27 and the shutter drive mechanism 26 to execute the exposure operation. At the same time, the image processing circuit 27 controls the image storage circuit 28 and the display circuit 29 to execute various processes on the acquired image signal, that is, signal processing for recording and display.

  When ending the shooting operation, the user turns off the power on / off button. Then, the power on / off switch 30e (see FIG. 2) linked to the power on / off button is activated to generate a power off signal, and this power off signal is transmitted to the control circuit 20. In response to this, the control circuit 20 drives the optical system driving mechanism 24 to cause the lens barrel 12 (shooting optical system 12a) set to an arbitrary focal length to be the shortest focus position which is the initial position in the shooting preparation state. Then, move to the retracted state. The operation of the lens barrel 12 and the like at this time is as follows.

  That is, for example, in the state where the lens barrel 12 is set to an arbitrary focal length, such as the state of FIG. 4, when the optical system driving mechanism 24 is driven, the rotating frame 32 rotates in a predetermined direction (retraction direction). . At this time, the male helicoid 32 a of the rotating frame 32 is in a state of being engaged with the circumferential groove 31 c of the fixed frame 31. When the rotating frame 32 rotates by a predetermined amount, the male helicoid 32a and the circumferential groove 31c are disengaged. The male helicoid 32 a meshes with the female helicoid 31 a of the fixed frame 31. When the rotation frame 32 continues to rotate in the same direction, the rotation frame 32 is retracted toward the rear in the direction along the optical axis O1 while rotating with respect to the fixed frame 31. As the rotary frame 32 is retracted, the rectilinear frame 34 and the first group frame 33 also move in the same direction.

  Further, along with the retraction operation of the rotating frame 32 at this time, the pressing pin 34d presses the mirror frame 35 backward. Therefore, the mirror frame 35 has an arrow R in FIGS. 3 and 4 with the support shaft 35a as the center of rotation against the urging force of the urging member 36 as the rotating frame 32 is retracted backward. It is a direction along the direction and turns clockwise.

  When the rotation frame 32 is retracted by a predetermined amount and the retraction operation of the rotation frame 32 is stopped, the mirror frame 35 also stops its rotation at a predetermined position (position in FIG. 3). In this stopped state, the mirror frame 35 is in a state where one end is in contact with the pressing pin 34d by the urging force of the urging member 36. Thereby, the urging | biasing to the rotation direction of the mirror frame 35 is controlled, and the mirror frame 35 is positioned in the position (position shown in FIG. 3). At this time, the reflecting mirror 22b of the mirror frame 35 is in a state of being retracted from the optical axis O1 and the optical axis O2. In this way, the electronic imaging apparatus 1 is set in the retracted state.

  At this time, the first lens group 21 and the second lens group 22a are stored in the fixed frame 31. At least the second lens group 22a is configured to be housed in a space after the reflecting mirror 22b has moved to the retracted position outside the optical path.

  As described above, according to the first embodiment, when the photographing state is set, the second lens group 22a of the second optical system 22 is fixed, and the first lens group 21 and the image sensor unit 23 are fixed. Is moved along the optical axes O1 and O2, so that the zooming operation is performed. Therefore, the mechanism for moving the first lens group 21 back and forth can be simplified. Therefore, the structure of the lens barrel unit 51 in the electronic imaging device 1 can be simplified without hindering the downsizing and thinning of the electronic imaging device 1 itself.

  In the retracted state, the mirror frame 35 holding the reflecting mirror 22b is disposed at a position retracted from the optical axis O1 and the optical axis O2, and at least the second lens group 22a is disposed in the space after the reflecting mirror 22b is retracted. Is configured to be stored. Thereby, the internal space of the electronic imaging device can be used more effectively than the conventional retractable type. Accordingly, the thickness of the electronic imaging device 1 itself can be reduced.

  In addition, the second lens group 22a is fixed at the photographing position, and the first lens group 21 and the image sensor unit 23 are displaced with respect to the second lens group 22a to perform a zooming operation. The amount can be reduced. As a result, the lens barrel can be reduced in size, particularly reduced in thickness.

  Furthermore, since the image sensor unit 23 is disposed within the dimension of the fixed frame 31 in the direction of the optical axis O1, the configuration in which the image sensor unit 23 is displaced in the direction of the optical axis O2 can also be configured in the direction of the optical axis O1 of the lens barrel. Does not increase dimensions.

  In the electronic imaging apparatus 1 of the above-described embodiment, the optical path bending optical system that bends the optical path of the light beam transmitted through the first lens group 21 and the second lens group 22a to the side of the imaging element 23a. The reflecting mirror 22b, which is a surface mirror having a reflecting surface, is used. However, it is not limited to such a form. For example, as shown in FIG. 7, a prism 22Ab can be employed instead of the reflecting mirror 22b in the first embodiment described above.

  FIG. 7 is a conceptual diagram illustrating a modification of the photographing optical system in the electronic image pickup apparatus according to the embodiment of the present invention, and illustrating the action of the photographing optical system and the image pickup element when the zooming operation is executed.

  In this case, FIG. 7A shows a short focus state of the photographing optical system 12a (variable magnification lens system). FIG. 7B shows the long focus state of the photographing optical system 12a (variable magnification lens system). FIG. 7C shows a state in which the photographing optical system 12a (variable magnification lens system) is stored inside the electronic imaging apparatus 1A, that is, a retracted state.

  As shown in FIG. 7, in the case of this modification, the second lens group 22A, which is the second optical system, is formed by the optical lens 22Aa and the prism 22Ab. At least one surface of the prism 22Ab is formed by a curved surface that is rotationally symmetric with respect to the optical axis.

  An aperture stop 34c is provided on the front side of the optical lens 22Aa. A shutter mechanism 26a is disposed at the gap on the exit surface of the prism 22Ab, that is, at a portion between the prism 22Ab and the image sensor 23a.

  The second lens group 22A including the aperture stop 34c and the shutter mechanism 26a is fixed inside the electronic imaging apparatus 1A when in the photographing state shown in FIGS. 7A and 7B. .

  In this state, when the zooming operation or the focus adjustment operation is executed, the first lens group 21 and the image sensor unit 23 are respectively connected to the first group drive unit (not shown; see reference numeral 24a in FIG. 2) and the imaging. It is driven by a system driving mechanism (see reference numeral 25 in FIG. 2). Thereby, the movement control of the 1st lens group 21 and the image pick-up element unit 23 is carried out in the direction along an optical axis.

  On the other hand, when the electronic imaging apparatus 1A is in the retracted state at the time of non-photographing, it is as shown in FIG. At this time, the prism 22Ab of the present modification and the second lens group 22A, which is the second optical system including the prism 22Ab, differ from the reflecting mirror 22b in the above-described embodiment, while maintaining the fixed state. Only one lens group 21 is retracted by being retracted, and is stored inside the electronic imaging apparatus 1A. About another structure, it is substantially the same as that of the above-mentioned one Embodiment.

  According to the modified example configured as described above, the prism 22Ab is adopted as means for configuring the optical path bending optical system, and the second lens group 22A, which is the second optical system including the prism 22Ab, is provided inside the electronic imaging apparatus 1A. Fixed placement. Therefore, in this respect, it differs from the reflecting mirror 22b provided so as to be retractable in the above-described embodiment. Thus, in the present modification, the first lens group 21 and the image sensor unit 23 move in the optical axis direction during zooming operation, and only the first lens group 21 moves in the optical axis direction during collapsing operation. The drive mechanism for driving these can be further simplified.

1 is a perspective view showing a schematic appearance of an electronic imaging apparatus according to an embodiment of the present invention. The block block diagram which shows the schematic internal structure of the electronic imaging device of FIG. FIG. 2 is a longitudinal sectional view showing a lens barrel unit of the electronic imaging apparatus of FIG. 1 and showing a retracted state. FIG. 2 is a vertical cross-sectional view showing a lens barrel unit of the electronic image pickup apparatus of FIG. The conceptual diagram which shows the effect | action of an imaging optical system and an image pick-up element unit when performing a scaling operation in the electronic imaging device of FIG. The figure which shows the effect | action of an imaging optical system and an image pick-up element when performing zooming operation in the electronic imaging device of FIG. 1, and shows the conceptual diagram of FIG. 5 according to this embodiment. The conceptual diagram which shows the modification of the imaging | photography optical system in the electronic imaging device of one Embodiment of this invention, and shows the effect | action of an imaging | photography optical system and an image pick-up element when a zooming operation is performed. The conceptual diagram which shows the positional relationship of an imaging optical system and an image pick-up element unit when a magnification operation is performed in the conventional electronic imaging device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1A …… Electronic imaging device 10 …… Exterior member 12 …… Lens barrel 12a, 112a …… Shooting optical system 13 …… Release button 14 …… Magnification operation lever 15 …… Operation mode switching button 16 …… Flash Light emitting window 20... Control circuit 21, 121... First lens group 22, 22 A, 122... Second lens group 22 a, 22 Aa ... Optical lens 22 b ... Reflector 22 Ab ... Prism 23, 123. Unit 23a …… Image sensor 23b …… Cover glass 23c …… Low pass filter 24 …… Optical system drive mechanism 24a …… First group drive unit 24b …… Second group drive unit 25 …… Imaging system drive mechanism 25a …… Stepping Motor 25b …… Lead screw 25c …… Nut 25d …… Fixing base 26 …… Shutter drive mechanism 26a …… Shutter mechanism 26b …… Sh Jatter cover member 27 …… Image processing circuit 28 …… Image storage circuit 29 …… Display circuit 30a …… Zoom switch 30b …… First (1st) release switch 30c …… Second (2nd) release switch 30d …… Mode switch 30e …… Power ON / OFF switch 31 …… Fixed frame 31a …… Female helicoid 31b …… Straight groove 31c …… Surrounding groove 32 …… Rotating frame 32a …… Male helicoid 32b …… Surrounding groove 32c …… Cam groove 33 for the first group frame …… Group 1 frame 33a …… Cam follower 34 …… Straight frame 34a …… Straight key 34b …… Bayonet claw 34c …… Aperture stop 34d …… Pressing pin 34e …… Straight groove 35 …… Mirror frame 35a …… Spindle 36 …… Biasing member 37 …… Lid member 37a …… Screw 41 …… Image sensor unit housing portion 41a, 41b …… Fixing member 41c …… Penetration Through-hole 42 …… Lid member 42a …… Screw 43 …… Image sensor unit holding frame 43a …… First support arm 43b …… Through hole 43c …… Second support arm 43d …… Groove 44 …… Guide shaft 45 …… Non-rotating shaft 46 ... Coil spring 51 ... Lens barrel unit agent Patent attorney Susumu Ito

Claims (10)

A first optical system that is disposed closest to the subject and allows a light beam from the subject to enter and pass therethrough, a second optical system that bends the optical path of the light beam that passes through the first optical system, and the first optical system And an electronic imaging device comprising an imaging element that receives an optical image of a subject formed through the second optical system and converts the optical image into an electrical signal.
When the Hare of Oko zooming operation while fixing the second optical system, characterized that you have the driving means Before moving the said first optical system and the image pickup device along the optical axis Electronic imaging device.   The electronic imaging apparatus according to claim 1, wherein the second optical system includes a surface mirror having a reflecting surface that bends the optical path.   3. The surface mirror is provided so as to be retractable out of an optical path, and at least a part of the second optical system can be accommodated in a space after the surface mirror is retracted. The electronic imaging device described. The second optical system has a lens group that is displaced at least between a storage position and a photographing position,
This lens group is integrally provided with a shutter mechanism,
The electronic imaging apparatus according to claim 1, wherein the shutter mechanism is movably disposed together with the lens group.   The electronic imaging apparatus according to claim 1, wherein the second optical system includes a prism that bends the optical path.   The electronic imaging apparatus according to claim 6, wherein at least one surface of the prism is formed by a curved surface that is rotationally symmetric with respect to an optical axis.   The electronic imaging apparatus according to claim 6, wherein the shutter mechanism is disposed at a portion between the prism and the imaging element.   An optical system driving mechanism that moves at least a part of the first optical system and the second optical system along an optical axis; and an imaging system driving mechanism that moves the imaging element along the optical axis. The electronic imaging apparatus according to claim 1, wherein:   In the focus adjustment operation, the first optical system and the second optical system are fixed, and the focus adjustment operation is performed by moving the image sensor along the optical axis. The electronic imaging device according to claim 1. A first optical system located closest to the object side;
A second optical system for bending the optical path of the first optical system;
An image sensor disposed on the optical path after being bent by the second optical system;
Driving means for driving the first optical system and the image sensor for zooming operation and driving the image sensor for focus adjustment;
An electronic imaging apparatus comprising:

Images